I know Servotronic is an option when you buy but I already go my 2014 X1 x128 last week and kinda feeling that I might have wanted the Servotronic option Is this something that can be added on?

Or is there any other way a BMW service center can loosen the steering atleast a bit?

There is no way to "loosen" the steering unless Servotronic is just a software change and it's doubtful that a dealer would recode. Make sure your tires are fully inflated as low pressure would cause higher steering effort. If you can handle the slightly rougher ride, go a few PSI above the recommended pressure settings. But just a few as overinflation can be bad for tire life and will cause extra wear on the center of the tread.